Salamander

This is a fork rattlegram v1.17 that is designed to work in browser using WASM, it also comes with a commandline tool that uses json.

You can use it now HERE

System dependencies

Building the command line tools requires a C++17 compiler andmake

Ubuntu:

sudo apt-get install build-essential

To produce the WebAssembly version, install Emscripten

sudo apt install emscripten

Command-line interface

Encode

Supply a json file, message is required.

{"message": "Hello"}

Key	Description	Default
message	text to transmit	(required)
callsign	up to 9 characters	N0CALL
carrierFrequency	carrier offset in Hz	1500
noiseSymbols	number of noise symbols to prepend	0
fancyHeader	enable the fancy header	false
sampleRate	one of 8000, 16000, 32000, 44100 or 48000	48000
channel	0 for mono, 1 left, 2 right, 4 I/Q	0

Example with all fields:

{
  "message": "Hello",
  "callsign": "N0CALL",
  "carrierFrequency": 1500,
  "noiseSymbols": 0,
  "fancyHeader": false,
  "sampleRate": 48000,
  "channel": 0
}

Run the encoder with:

rgcli encode output.wav payload.json

Decode

Decoding a WAV file outputs the json

rgcli decode input.wav [channel]

WebAssembly build

Running make wasm generates web/rgcli.mjs and web/rgcli.wasm

If you just want the web app running locally and you don't have time for all of the above, go to the releases section and download the latest release, unzip it, cd to folder, and launch a local webserver with python.

python3 -m http.server

then browse to

http://localhost:8000

If you are on windows and don't have python you can use this powershell script (included in the release)